Bayer Leverkusen claimed a hard fought 2-1 victory over 10-man Mainz on Friday to go 11 points clear at the top of the Bundesliga and extend their unbeaten run to German record 33 matches. Robert Andrich scored the winner in the 68th minute with a lot of help from Mainz goalkeeper Robin Zentner, who failed to hold on to the shot from a distance after earlier making several big saves. Leverkusen had led from Granit Xhaka’s third minute stunner into the far top corner, his first goal since a summer move from Arsenal. Dominik Kohr levelled five minutes later as second last Mainz made life difficu…